RPM (grinder speed)

Revolutions per minute of the burrs during operation. Commercial AC-motor grinders typically run at 1400 RPM. High-end DC-motor grinders run at 400–900 RPM. Some can be programmed.

Why it matters — Lower RPM means less heat in the burrs (which preserves volatile aromatic compounds), less burr chatter, and — some argue — better flavour clarity. The trade-off is slower dosing.

Good to know

• Heat-sensitive coffees (light roasts, anaerobics) often benefit from lower-RPM grinders.
• Higher RPM matters more in commercial settings where dose speed during a rush outweighs marginal flavour differences.